/*
 * $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk/module-client/src/main/java/org/apache/http/conn/ClientConnectionOperator.java $
 * $Revision: 645850 $
 * $Date: 2008-04-08 04:08:52 -0700 (Tue, 08 Apr 2008) $
 *
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.http.conn;

import java.io.IOException;
import java.net.InetAddress;

import org.apache.http.HttpHost;
import org.apache.http.conn.scheme.SocketFactory;
import org.apache.http.params.HttpParams;
import org.apache.http.protocol.HttpContext;

/**
 * Interface for opening {@link OperatedClientConnection connections}. This
 * interface encapsulates the logic to create sockets and to open or update the
 * connection with the new socket. Implementations will most likely make use of
 * {@link SocketFactory socket factories}. <br/>
 * The methods in this interface allow the creation of plain and layered
 * sockets. Creating a tunnelled connection through a proxy, however, is not
 * within the scope of the operator.
 * 
 * @author <a href="mailto:rolandw at apache.org">Roland Weber</a>
 * 
 * 
 *         <!-- empty lines to avoid svn diff problems -->
 * @version $Revision: 645850 $ $Date: 2008-04-08 04:08:52 -0700 (Tue, 08 Apr
 *          2008) $
 * 
 * @since 4.0
 */
public interface ClientConnectionOperator {

    /**
     * Creates a new connection that can be operated.
     * 
     * @return a new, unopened connection for use with this operator
     */
    OperatedClientConnection createConnection();

    /**
     * Opens a connection to the given target host.
     * 
     * @param conn
     *            the connection to open
     * @param target
     *            the target host to connect to
     * @param local
     *            the local address to route from, or <code>null</code> for the
     *            default
     * @param context
     *            the context for the connection
     * @param params
     *            the parameters for the connection
     * 
     * @throws IOException
     *             in case of a problem
     */
    void openConnection(OperatedClientConnection conn, HttpHost target,
            InetAddress local, HttpContext context, HttpParams params)
            throws IOException;

    /**
     * Updates a connection with a layered secure connection. The typical use of
     * this method is to update a tunnelled plain connection (HTTP) to a secure
     * TLS/SSL connection (HTTPS).
     * 
     * @param conn
     *            the open connection to update
     * @param target
     *            the target host for the updated connection. The connection
     *            must already be open or tunnelled to the host and port, but
     *            the scheme of the target will be used to create a layered
     *            connection.
     * @param context
     *            the context for the connection
     * @param params
     *            the parameters for the updated connection
     * 
     * @throws IOException
     *             in case of a problem
     */
    void updateSecureConnection(OperatedClientConnection conn, HttpHost target,
            HttpContext context, HttpParams params) throws IOException;

} // interface ClientConnectionOperator

